Real-Time Observation and Analysis of Single-Domain YBCO Bulk Superconductor by TSIG Process

The growth process of single domain YBCO bulk superconductor by top-seeded infiltration and growth technique has been observed in real time by an in situ high temperature video camera. The initial epitaxial growth temperature from the NdBCO seed and growth rate of a single domain YBCO bulk were obtained by measuring the growth distance between the seed and the growing interface at different times. It was found that the initial epitaxial growth temperature of YBCO crystal is about 1008 °C; the average growth rate (R a) is increasing with time at first, reaches a highest value about 0.28 mm/h in the range of under cooling temperature(ΔT) 18–20 °C, and decreases to 0.26 mm/h until the single domain YBCO bulk grown up to the whole sample at about ΔT = 22 °C. In addition, It is also discovered that the instantaneous growth rate(Ri) is a random scattering data with time and ΔT, R i varies from 0.04 to 1.14 mm/h and without any order. These results were observed for the first time.